Fatigue and reliability evaluation of unnotched carbon epoxy laminates

An experimental test program has been carried out to verify the validity of a gen-eralised residual strength degradation model for tension-tension fatigue of unidirec-tionally reinforced unnotched carbon/epoxy composites. Further, the model is used for predicting the effect of a prior high load on the fatigue behaviour of these laminates. It is verified in the present program that a specimen is guaranteed to survive a certain minimum number of load cycles as predicted by the model after it has sur-vived a proof load prior to fatigue. The correlation between statistical distributions of the fatigue life and the residual strength as predicted by the model and those deter-mined experimentally, including the effect of proof load, is found satisfactory